This invention relates generally to input devices for a computer, and more particularly, to a manually controlled pointing device for a computer, such as a mouse.
A computer mouse is a common pointing device used to generate movement commands for controlling a cursor position displayed on a computer screen. The mouse sits to the side of the computer and resides on a flat surface, such as a mouse pad. Typically the mouse requires a substantially planar surface on which to move. A mechanical mouse includes a captured ball at an underside which rolls along the planar surface as an operator moves the mouse. The movement of the ball generates inputs to respective x,y directional sensors housed adjacent to the ball within the mouse. The x,y directional signals are input to the computer to control the cursor movement. Another kind of mouse, an optical mouse, includes a light emitting diode or phototransistor associated with a grid and providing a signal corresponding to distance and direction of mouse movement.
A computer mouse often includes one or more buttons which are either dedicated or programmed to correspond to specific command functions, (e.g., "click" to select a display icon; "double click" or open item corresponding to display icon; display a menu; drag icon to a new location on the screen; or some custom function). Other common computer pointing devices include a trackball, a touch pad, and a joy stick. Each of such devices controls movement of a cursor on a computer screen and include buttons for entering specific command functions.
Conventionally, the mouse is tethered to a host computer by a cable, or another flexible or rigid linking mechanism. One undesired effect of the cable is that it restricts movement of the mouse.
Another shortcoming of the conventional mouse relates to portable computing. A large portion of the personal computer market is for portable computers, such as laptop computers, notebook computers, sub-notebook computers and hand-held or palmtop computers. The mouse is a tethered device, so it typically is detached and stored in a carrying case with the portable computer. Such mouse takes up scarce space in the carrying case.
In commonly assigned U.S. Pat. No. 5,428,355 a flexible linking mechanism connects the mouse to the host computer. This flexible linking mechanism is part of the tracking device, the remainder of which is contained inside the computer. This type of tracking device is acceptable only for computers that have space available for containment of the tracking device and storage for the mouse. Accordingly, there is a need for a computer mouse which overcomes these shortcomings.